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31.
Failure-free survival, defined as the absence of relapse, non-relapse mortality or addition of another systemic therapy, has been proposed as a potential endpoint for clinical trials, but its use has only been reported for single-center studies. We measured failure-free survival in a prospective observational cohort of patients (n=575) with both newly diagnosed and existing chronic graft-versus-host disease from nine centers. Failure was observed in 389 (68%) patients during the observation period. The median follow up of all patients was 30.9 months, and the median failure-free survival was 9.8 months (63% at 6 months, 45% at 1 year, and 29% at 2 years). Of the variables measured at enrollment, ten were associated with shorter failure-free survival: higher National Institutes of Health 0–3 skin score, higher National Institutes of Health 0–3 gastrointestinal score, worse range of motion summary score, lower forced vital capacity (%), bronchiolitis obliterans syndrome, worse quality of life, moderate to severe hepatic dysfunction, absence of treatment for gastric acid, female donor for male recipient, and prior grade II–IV acute graft-versus-host disease. Addition of a new systemic treatment, the major cause of failure, was associated with an increased risk of subsequent non-relapse mortality (hazard ratio=2.06, 95% confidence interval: 1.29–3.32; P<0.003) and decreased survival (hazard ratio=1.51, 95% confidence interval: 1.04–2.18; P<0.03). These results show that fewer than half of patients on systemic treatment will be failure-free survivors at 1 year, and fewer than a third will reach 2 years without experiencing failure. Better treatments are needed for chronic graft-versus-host disease. Clinicaltrials.gov identifier: NCT00637689.  相似文献   
32.
Jansen  J; Ash  RC; Zanjani  ED; LeBien  TW; Kersey  JH 《Blood》1982,59(5):1029-1035
Monoclonal antibody BA-1 binds to B lymphocytes, to cells from most cases of non-T acute lymphoblastic leukemia (ALL), and weakly to neutrophils. To determine whether BA-1 also reacts with hematopoietic progenitor cells (HPC), we studied the effect of removal of BA-1+ cells from human bone marrow on the proliferation in vitro of the trilineage precursor cell CFU-GEMM, and on the committed progenitor cells of granulopoiesis (CFU-C) and erythropoiesis (BFU-E/CFU-E). Complement- mediated cytotoxicity using BA-1 at concentrations far beyond those required to lyse BA-1+ bone marrow cells and ALL cells did not result in inhibition of colony formation in any of the assays. A rosette separation method, using ox red blood cells coated with BA-1, resulted in enrichment of HPC in the BA-1-depleted interface, whereas very few HPC were found in the BA-1-enriched pellet. Both methods indicate that BA-1 does not bind to HPC, although binding of the antibody to the lymphohematopoietic stem cell cannot be excluded yet. The high cytotoxic capacity of the IgM antibody BA-1, and the lack of reactivity with HPC, make the antibody particularly suitable for use in autologous bone marrow transplantation for patients with ALL.  相似文献   
33.
The present study in patients with aplastic anemia was undertaken to determine whether exposure of recipients to donor blood products 24 hr before preparation with cyclophosphamide (1) enhanced the rate of sustained engraftment of marrow from HLA-identical siblings as suggested by animal experiments, (2) increased the rejection rate, in particular in transfused patients who may already have been exposed to donor antigens by blood products, or (3) was of no relevance to the outcome of transplantation of marrow from HLA-identical siblings. One- hundred fifty-five patients were studied, of whom 78 received blood products from the marrow donor 24 hr before cyclophosphamide and 77 did not. A binary logistic regression analysis was applied to the data, simultaneously considering five previously known risk factors for rejection. Results showed that preceding transfusion of donor blood products had neither a significant beneficial nor detrimental effect on the incidence of sustained engraftment.  相似文献   
34.
Sanders  JE; Thomas  ED; Buckner  CD; Doney  K 《Blood》1987,70(1):324-326
Fifty-seven children between the ages of 3 and 17 years with acute lymphoblastic leukemia (ALL) in chemotherapy-induced second bone marrow remission were given cyclophosphamide, total body irradiation, and bone marrow transplants from HLA-matched donors. Sixteen died of transplant- related complications. Eighteen relapsed between 56 and 833 days after transplantation, and 16 died of leukemia. Two survive in remission off treatment following chemotherapy. Twenty-three survive in continuous remission from 1.4 to 10.4 years after transplantation and the actuarial analysis shows disease-free survival of 40% with a plateau extending from 2.5 to 10.4 years.  相似文献   
35.
Loss of a whole chromosome 7 or a deletion of the long arm, del(7q), are recurring abnormalities in malignant myeloid diseases. To determine the location of genes on 7q that are likely to play a role in leukemogenesis, we examined the deleted chromosome 7 homologs in a series of 81 patients with therapy-related or de novo myelodysplastic syndrome or acute myeloid leukemia. Our analysis showed that the deletions were interstitial and that there were two distinct deleted segments of 7q. The majority of patients (65 of 81 [80%]) had proximal breakpoints in bands q11-22 and distal breakpoints in q31-36; the smallest overlapping deleted segment was within q22. The remaining 16 patients had deletions involving the distal q arm with a commonly deleted segment of q32-33. To define the proximal deleted segment at 7q22 at a molecular level, we used fluorescence in situ hybridization with a panel of mapped yeast artificial chromosome (YAC) clones from 7q to examine 15 patients with deletion breakpoints in 7q22. We determined that the smallest overlapping deleted segment is contained in a well- defined YAC contig that spans 2 to 3 Mb. These studies delineate the region of 7q that must be searched to isolate a putative myeloid leukemia suppressor gene, and provide the necessary cloned DNA for more detailed physical mapping and gene isolation.  相似文献   
36.
Shiota  Y; Wilson  JG; Harjes  K; Zanjani  ED; Tavassoli  M 《Blood》1993,82(5):1436-1444
The adhesion of hematopoietic progenitor cells to bone marrow stromal cells is critical to hematopoiesis and involves multiple effector molecules. Stromal cell molecules that participate in this interaction were sought by analyzing the detergent-soluble membrane proteins of GBI/6 stromal cells that could be adsorbed by intact FDCP-1 progenitor cells. A single-chain protein from GBI/6 cells having an apparent molecular weight of 37 Kd was selectively adsorbed by FDCP-1 cells. This protein, designated p37, could be surface-radiolabeled and thus appeared to be exposed on the cell membrane. An apparently identical 37- Kd protein was expressed by three stromal cell lines, by Swiss 3T3 fibroblastic cells, and by FDCP-1 and FDCP-2 progenitor cells. p37 was selectively adsorbed from membrane lysates by a variety of murine hematopoietic cells, including erythrocytes, but not by human erythrocytes. Binding of p37 to cells was calcium-dependent, and was not affected by inhibitors of the hematopoietic homing receptor or the cell-binding or heparin-binding functions of fibronectin. It is proposed that p37 may be a novel adhesive molecule expressed on the surface of a variety of hematopoietic cells that could participate in both homotypic and heterotypic interactions of stromal and progenitor cells.  相似文献   
37.
Eight patients with Fanconi's anemia were given cyclophosphamide alone (seven patients) or combined with procarbazine and antithymocyte globulin (one patient) followed by marrow grafts from HLA-identical siblings. All patients had engraftment. Seven developed acute and three chronic graft-versus-host disease (GVHD). Three patients died with GVHD and infectious complications (days 19, 56, and 82) and one with an intracerebral hemorrhage (day 540). Four patients are surviving 647- 3435 days after grafting, two are well, and two have chronic GVHD that is improving. These results show that Fanconi's anemia can be treated successfully by allogeneic marrow transplantation.  相似文献   
38.
In normal vision, the inputs from the two eyes are integrated into a single percept. When dissimilar images are presented to the two eyes, however, they compete for perceptual dominance, so that one eye's view suppresses that of the other. Recent evidence suggests that this phenomenon, known as binocular rivalry, arises through competition between alternative stimulus interpretations in extrastriate cortex. Because eye-specific information appears to be lost at this stage, it remains unclear how the stimulus conditions that yield binocular rivalry are distinguished from those that produce stable single vision. Using a neural network that models the mammalian early visual system, I investigate here the hypothesis that congruent and conflicting stimuli are distinguished by their different effects on the relative timing of action potentials in primary visual cortex (V1), where monocular inputs are first combined. In the model, congruent stimulation of both eyes results in synchronization of discharges among binocular neurons in V1. By contrast, conflicting stimulation of the two eyes results in neuronal asynchrony in this area. This asynchrony then produces rivalrous response suppression at later stages in the visual pathway. Synchronization of firing in V1, however, prevents such competition, thereby ensuring non-rivalrous responses. These novel effects of spike timing on competition emerge naturally from the network dynamics. The results suggest that input-related differences in relative spike timing at an early stage of visual processing may play an important part in the phenomena both of binocular integration and rivalry; furthermore, they indicate that the temporal patterning of cortical activity may be a fundamental mechanism of selection among competing stimulus representations.   相似文献   
39.
This study compares government records of death by suicide, in Northern Ireland, during two quinquennia in the decade 1982–1991. Specifically these quinquennia are 1982–1986 l 1987–1991. During the latter quinquennium there was an increse m rate for males in most age groups, except the 45–54 and the over 65 years age groups. However, females had an increased rate in the 15–24 and 35–54 years age groups, but have a decreased rate in the other age groups. There has been a decrease in the rate of suicides by poisoning with solids and liquids for both sexes. However, male suicide rates by more violent methods have increased substantially during the latter quinquennium. Three cohorts of males, those in the 15–24, 25–34, and 55–64 age groups, have shown substantial increases during the latter quinquennium. Suggestions for psychiatric intervention strategies are made.  相似文献   
40.
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